Part 3/9:
Observations indicate that galaxies are rotating at speeds that would typically cause them to disintegrate under the force of gravity unless some unseen mass is acting upon them. The proposed dark matter fills this gap. However, despite extensive searching, no definitive evidence has been found for dark matter particles.
Quantized Inertia: A Potential Alternative
Mike McCulloch suggests an alternative explanation, termed quantized inertia (QI), which reexamines the fundamental concepts of inertia and motion. QI posits that inertial mass arises due to variations in a quantum vacuum field—essentially, variations in the radiation the object experiences depending on its acceleration and the presence of horizons.